Two of these characters are returning from the first Mass Effect game.Photo by BioWare

Film critics have decried the disease of sequel-itis since the Hollywood blockbuster era began more than 30 years ago. They bemoan the lack of originality, the reliance on popular themes and characters, and the sheeplike masses who flock to repeated installments of their favorite franchises. Video games have been onboard with the idea of sequels almost from the very start (remember Ms. Pac-Man?), but the idea of creating cash-generating franchises has taken on new importance in an increasingly hit-driven environment.

So, it's only natural for some industry watchers to bemoan the likes of Mass Effect 2, Halo 3, BioShock 2, Assassin's Creed 2, and others. But, judging from recent experience, the real problem is not that these games share too much with movie sequels, it's that they're not enough alike.

Having played nearly every notable recent and upcoming video game sequel, it's clear that the hubris of game developers and publishers is having a potentially audience-sapping effect--their unquestioned assumption is that you not only played the original game a new sequel is based on, but also finished it, and can clearly remember every plot twist up to two years later. This blindness to anything but the uber-fan audience is a disservice to the very mainstream game buyers who keep the entire industry afloat.

The incredibly plot-driven Mass Effect 2 (out January 26) will import your character from the first game, but if you come in cold, there are only sporadic references to all the twists and turns of the original, and the very intricate web of alien cultures, politics, and history that provides the motivations for the main characters.

Playing Assassin's Creed 2, it's obvious that a newcomer to the series would be completely lost as to even the point of the game (which involves medieval virtual reality settings and "Da Vinci Code"-like secret societies). Having played, but not finished, the original two years ago, I was forced to head to Wikipedia for a refresher course on what was happening and why. The early versions of BioShock 2we've played have the same fatal flaw, assuming an intimate familiarity with the settings and themes of the original (which is still especially worth going back and playing if you haven't already).

Even the venerable Halo franchise suffers from this malady. Halo 3 may have been one of the biggest game launches everwhen it was originally released in 2007, but it kicks right in with no explanation of the story so far, or explanation of who these various factions fighting each other are. Still, as the game was so multiplayer focused, and even the single-player game required only a quick trigger finger to enjoy, even newcomers to the franchise could settle in relatively easily.

Fighting a Big Daddy in BioShock 2.Photo by 2K Games

If one looks at the Hollywood model, film sequels invariably start with (sometimes long-winded) exposition about previous events, or maybe a flashback/recap of the earlier entries. The other option is to keep the new story separate enough so that little previous knowledge is required. The recent "Star Trek" reboot is a great example of that.

The goal for a big-budget sequel is to attract a bigger audience than its predecessor, and not to limit itself to serious fans who saw the original, then bought the collector's edition Blu-ray. A handful of examples: "Terminator 2" was seen by many more people than "The Terminator," and through a combination of recaps and clever writing, didn't require you to run out to the local video store to figure out what was going on. "The Dark Knight" did better business than "Batman Begins," but new audiences could easily come in cold and enjoy the film with only a passing casual familiarity with the caped crusader.

In the otherwise excellent Mass Effect 2, however, the action picks right up, and if you were not familiar with the ancient alien technology and apocalyptic visions of the original, I can't imagine being able to see the game as anything other than a series of disconnected firefights. There is an in-game encyclopedia one can reference, but setting aside 20 minutes of each play session for library research may not be the secret formula for mainstream success.

The solution is easy: gamemakers should realize their sequel's ideal audience is someone who perhaps heard the previous game in a series was cool, and is willing to invest in the new installment, sight unseen. That's a serious vote of consumer confidence, and accommodating these new customers will help ensure that Part 2 of your game franchise leads to a Part 3 and beyond.